Merocarbocyanine dyes containing a cycloalkyl group on the dimethine chain



Patented May 11, 1948 UNITED (STATES PATENT oFFic MEROCARBOCYANINE DYES CONTAINING A CYCLOALKYL GROUP ON THE DIMEIHINE CHAIN Leslie G. S. Brooker and Grafton H. Keyes, Rochester, N. Y., assignors to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey No Dawn... Application June 1, 1945,

Serial No. 597,150

Claims. 1

containing a cycloalkyl group on the dimethine chain and have found that certain of these new dyes (those containing a cyclopropyl group on the dimethine chain) are stronger sensitizers of photographic silver halide emulsions than the known merocarbocyanine dyes containing on the dimethine chain a straight chain alkyl group of equal carbon content.

It is, accordingly, an object of our invention to provide merocarbocyanine dyes having a cyclo-, alkyl group on the dimethine chain and to provide a process for the preparation thereof. A further object is to provide photographic emulsions sensitized with such dyes. Other objects will become apparent hereinafter. V

The dyes of our invention can be presented by the following general formula:

R1 R-iI-o'=0H-c='oo'=o wherein R represents an alkyl group (i. e. alcohol radical), R1 represents a cycloalkyl group containing from 3 to 6 carbon atoms in the ring, Q represents the non-metallic atoms necessary to complete a E-membered heterocyclic or a 6-mem- 'bered heterocyclic nucleus, e. g, a 2-thio-2,4(3,5)

thiazoledione nucleus (e. g. rhodanine, 3-ethylrhodanine or 3-phenylrhodanine), a 2,4(3,5)- thiazoledione nucleus, a 2-thio-2,4(3,5) -oxazoledione nucleus, a 2-alkylmercapto-4(5) -thiazolone nucleus, a 2-diphenylamino 4(5) thiazolone nucleus, a 2-alkylphenylamino-4(5)-thiazolone nucleus, a 2-thio-2,4(3,5) -imidazoledione nucleus (e. g. thiohydantoin, 1,3-diethyl-2-thiohydantoin, a l-ethyl-3-phenyl-2-thiohydantoin,- a 1,3-diphenyl-2-thiohydantoin) a 2 alkylmercapto- 5(4) -imidazolone nucleus, a barbituric acid nucleus or a thiobarbituric acid nucleus, etc., and Z represents the non-metallic atoms necessary to complete a heterocyclic nucleus selected from the group consisting of those of the benzothiazole series, those of the benzoselenazole series, those 2 of the a-naphthothiazole series, those of the p-naphthothiazole series, those of the a-naphthoselenozole series and those of the p-naphthoselenazole series.

5 In accordance with our invention, we provide "the aforesaid merocarbocyanine dyes containing a cycloalkyl group on the dimethine chain by condensing a cyclammonium quaternary salt containing in a reactive position (i. e. the aor 1 'y-position) a fi-cycloalkyl-l3-alkylmercaptovinyl group with a heterocyclic compound containing 7 a ketomethylene (COCH2) group, especially heterocyclic compounds containing any of the following groups: COCH2O-, CQCH2S and COCH2--ND (wherein D represents hydrogen, alkyl or aryl, for example) in the ring, e. g. rhodanine, a 3-alkylrhodanine, a 3-phenylrhodanine, a 3-alkyl-2- thio-2,4(3,5)-oxazoledione, a 2-alkylmercapto- 4(5) -thiazolone, a 2-diphenylamino-4(5) -thiazolone, a 2-alkylphenylamino-4(5) -thiazolone, a

2-thio-2,4( 3,5) -imidazoledione nucleus (e. g. thiohydantoin,. 1,3-diethyl-2-thiohydantoin, l-ethyl- 3-phenyl-2-thiohydantoin or 1,3-diphenyl-2- thiohydantoin, a 2-alkylmercapto-5(4) -imidazolone, a thiobarbituric acid nucleus, etc). The aforesaid cyclammonium quaternary salts include those of the benzothiazole series, those of the benzoselenazole series, those of the a-naphthothiazole series, those of the ,B-naphthothiazole series, those of the m-naphthoselenazole series and those of the p-naphthoselenazole series.

The condensations are advantageously carried out in the presence of a basic condensing agent. Alcoholic solutions of tertiary amines, such as triethylamine, N-alkylpiperidines or pyridine are advantageously employed as basic condensing agents. Heat accelerates the condensations.

The following examples will serve to illustrate our new dyes and the manner of obtaining the same.

Example 1.3-et yl-5-[(3 ethyl 2(3) benzethiazolylidene) a cyclopropylethylidenel 2 mic-2,4 (3,5) -oa:azoledione C3H5 1.3 g. (1 mol.) of 2-cyclopropylthioformylmethylene-3-ethylbenzothiazoline and 1 g. (1 mol.) of methyl-p-toluenesulfonate were heated together at the temperature of a steam bath for 30 minutes. The inercapto intermediate thus formed was dissolved in 30 cc. of absolute ethyl alcohol and .7 g. of 3-ethyl-2-thio-2,4-(3,5)- oxazoledione. 1 g. (2 mol.) of triethylamine were '4 methyl alcohol and. dried. It was purified by re crystallization from methyl alcohol and obtained as reddish needles. Melting point 135-137 C.

Example 4. 3 ethyZ-5-[(3-ethyl.-2 (3) benzeadded. The mixture was refluxed for 15 minutes. 5 Dye separated on chilling. It was purified by igz ggggzg cyclopropylemylzdene] recrystallization from methyl alcohol and ob- S tained as scarlet needles with a blue reflex. z a Melting point 193-195 C. dec. '16 0:3

l Example 2. 3 ethyl -[(3-ethyl-2(3)-benzo- E S thiazolylidene) a cyclohexylethylidene] 2 CH2CH2 thin-2,4 (3,5) -oxazoledione I '13 g. (1 mol.) of 2-cyclopropylthioformyl- H methylene-3-ethylbenzothiazoline and 1 g. (1 2 5 mol.) of methyl-p-toluene-sulfonate were heated together'at'the temperature of a steam bath for 30 minutes. The mercapto intermediate thus f formed was dissolved in cc. of absolute ethyl 01H. 20 alcohol and .8 g. (1 mol.) of 3-ethylrhodanine, 1

.g. (2 mol.) triethylamine were added. This mix- 3 g. (1 mol.) of 2-cyclohexylthioforrnylmethylture was then heated un der reflux for 15 minutes. ene 3-ethylbenz0thiazo1ine and g. (1 mol.) Of Dye separated on chjlling was purified by remethyl-ptoluene-sulfonate were heatedtogethcrystallization from a mixture of pyridine and er on Steam bath for minutes- The 5 mcthylalcohol and obtained as metallic needles. capto intermediate thus formed wasdissolved in Mating m1; 197 19 C .30 CC. of absolute t yl alcohol; To this solu- In a, manner similar to that illustrated in the tion was added 1.45 g. (1.mol.) 3-ethyl 2-thioforegoing examples, aand p-naphthothiazole, -0XaZ01edi.0ne and 1 (1 t i y 0cand fl-naphthoselenazole andbenzoselenazole amine and the mixture refluxed for 15 minutes. 30 quaternary Salts containing 3-cy 31 a,]ky1-p a1- After chilling, the dye which had separated was kylmercaptovinyl group in the lZ-pOSitiOn can be Collected 0n fi t Washed with water,.methy1 alcondensed with heterocyclic compounds containcohol and dried. It .was purifiedby two recrys- [ing a 'ketomethylene group 'to give merocyanine tallizations from methyl alcohol. Melting point dyes. The following condensations are exem- 158-.160 C. 35 plan:

quaternary salt .ketornethylene compound 2 (18 cyclopropyl 6 --methylmercaptoviny1) benzothiazole n-buto p btoluenesulfonate.

o 5 chloro 2(5 cyclopropyl B ethylmercaptovinyl) benzo thiazole n propo p toluenesulfonate.

2 (B oyclobutyl B methylmercaptovinyl) benzoselenazole etho p tolnenesulfonate.

2 -(d cyclopropyl 5 methylmercaptovlnyl) benzothiazole'fi -ethoxyetho p 7 toluenesulionate.

2 -.(;8 -eyclopropyl :5 methylmercaptovinyl) benzoselenazole metho p toluenesuli'onate.

2 (13 r cyclopropyl -35 methylmereaptovinyl) -'B naphthothiazole ethop toluenesulfonate.

2 (B cyclopropyl 13 methylmercaptovinyD-a -naphthothiazole ethop tolnenesulfonate.

2 (8 cyclopropyl B n butylmercaptovinyl) B naphthoselenarole metho p toluenesulionate.

2 (9 cyclopropyl -fi methylmcreaptovinyl) benzothiazole etho 3 toluenesulfonate.

2 (p cyclopropyl 9 mcthylmercaptovinyl) benzothiazole allo p toluenesulfonate.

2 (B cyclopentyl B methylmercaptovinyl) benzothiazole ethiodide- 2 (fl cyclopropyl fl methylmercaptovinyl) benzothiazole etho p toluenesulfonate.

2 ethylphenylamino 4(5) thiazolone thioba rbituric acid. 3 phenylrhoclanine.

3 ethylrhodanine. rhodanine.

xEzmm-ple 3-ethyl 5 3-ethyl-2 3) -benzothiazolylz'denw a cyclobutylethylidene] --2 time-2,4 (3,5) -0a:azoledione Thus, to prepare 2- It was recrysv'llhezthioketonesafrom which the p-cycloalkyleealkylmereaptovinyl eompounds are prepared .are'desc'ribed incur-parent application Serial No.

5 515,978, as well as in the copending application of Grafton H. Keyes, Serial No. 597,149, filed of even date herewith (now United States Patent 2,429,469, dated October 21, 1947).

What we claim as our invention and desire to be secured by Letters Patent of the United States 1. The merocarbocyanine dyes which are represented by the following general formula:

wherein R represents an alkyl group, Z represents the non-metallic atoms necessary to complete a heterocyclic nucleus selected from the group consisting of those of the benzothiazole series, those of the benzoselenazole series, those of the u-naphthothiazole series, those of the p-naphthothiazole series, those of the a-naphthoselenazole series and those of the fl-naphthoselenazole series, and Q represents the non-metallic atoms necessary to complete a heterocyclic nucleus selected from the group consisting of 5-membered and S-membered heterocyclic nuclei.

2. The merocarbocyanine dyes which are represented by the following general formula:

wherein R represents a primary alkyl group containing from 1 to 4 carbon atoms, Z represents a heterocyclic nucleus of the benzothiazole series and Q represents the non-metallic atoms necessary to complete a heterocyclic nucleus of the rhodanine series.

3. The merocarbocyanine dyes which are represented by the following general formula:

wherein R represents a primary alkyl group containing from 1 to 4 carbon atoms, Z represents a heterocyclic nucleus of the benzothiazole series and Q represents the non-metallic atoms necessary to complete a heterocyclic nucleus of the 2-thio-2,4 (3,5) -oxazo1edione series.

4. The merocarbocyanine dye of the following formula:

5. The merocarbocyanine dye of the following formula:

6. The merocarbocyanine dyes which are represented by the following general formula:

CH CK) wherein R represents a primary alkyl group containing from 1 to 4 carbon atoms.

7. The merocarbocyanine dyes which are represented by the following general formula:

wherein R represents a primary alkyl group containing from 1 to 4 carbon atoms.

8. The merocarbocyanine dyes which are represented by the following general formula:

I Q\ R-i-Io'=oH-o='co=o =0 6H wherein R represents a primary alkyl group containing from 1 to 4 carbon atoms.

10. The merocarbocyanine dye which is represented by the following formula:

C=CH-C= 0:5

I C I 2 ulls 03H;

LESLIE G. S. BROOKER. 6o GRAFTON H. KEYES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,106,383 Schneider Jan. 25, 1938 2,165,338 Brooker July 11, 1939 

